The present invention relates to a connector for joining two tubes, typically pipe sections constructed of plastic, such as PVC, and more particularly to a method for enabling repair of tubing elements insitu in piping systems installed in a building structure. In particular the invention relates to modifying piping systems or repairing said piping systems characterized by low pressure plumbing joints between adjacent open ended tubes constructed of PVC material adapted for use in indoor plumbing systems.
It is recognized that repair requiring joining of butt-ends, and open ended tubing of piping insitu is difficult because, in order to gain adequate access to effect a repair, typically a substantial section of adjacent molding and wall paneling must be removed, thereby inflicting damage on the structure, typically walls of a room. The repair generally involves removing a section of piping, for making a new joint for replacement thereof due to damaged or leaky joint and manipulating a length of pipe, or alternatively to make changes in the piping system for adding or deleting pipe or changing the configuration thereof.
Applicant is aware of other prior art devices which provide for connectors for joining butting tubing elements. One such prior art device is U.S. Pat. No. 5,152,556 to Holland et. al, dated Nov. 6, 1992. Other prior art devices disclosing actually split connecting structures are disclosed in U.S. Pat. Nos. 4,236,736; 4,095,826; 3,352,575 and 1,283,554. The structure of U.S. Pat. No. 4,095,826 is particularly intended for joining rigid plastic pipe. U.S. Pat. Nos. 4,615,161; 4,266,164; 4,159,132; 3,224,795; and 3,041,088, describe other systems for joining open-end tubes together.
The formation of butt-joints in open-ended tubing is problematic, particularly when the joint is installed is not readily accessible i.e. being out in the open. Problems are exacerbated when the tubing is formed from materials which have a relatively low thread (shear) strength, such as plastic, ceramic, and/or carbon-carbon composites, which makes the formation of conventional threaded connections impractical. While compressible seals, such as 0-ring seals, can be utilized to improve the sealing characteristics of such a joint, composite materials are frequently not sufficiently strong to provide the desired compression of the seal ring when using conventional threaded end connectors.
It would therefore be desirable to provide connector designs, systems, and methods suitable for joining open-ended PVC tubing and pipes together when installed insitu buildings. The connectors should be relatively simple to manufacture and to put in place, and should be suitable for fabrication from most or all types of materials, including PVC. The connectors should include a include a seal element between the tubes being joined and should be able to provide sufficient compressive force to form an effective seal, even against water temperatures and pressure and the ranges of 80-100 PSI. Preferably, the connectors should provide both axial and radial compression of the seal to provide for joining of the PVC separate tubing elements.